On 2018-04-03T12:36:43 -0400
Brian Goetz <brian.go...@oracle.com> wrote:
>
> Here's one that I suspect we're not expecting to recover terribly well
> from: hierarchy inversion. Suppose at compile time A <: B. So the
> following is a sensible switch body:
>
> case String: println("String"); break;
> case Object: println("Object"); break;
>
> Now, imagine that by runtime, String no longer extends Object, but
> instead Object absurdly extends String. Do we still expect the above to
> print String for all Strings, and Object for everything else? Or is the
> latter arm now dead at runtime, even though it wouldn't compile after
> the change? Or is this now UB, because it would no longer compile?
I'm still giving thought to everything you've written, but I am
wondering: How feasible is it to get the above to fail early with an
informative exception/Error?
--
Mark Raynsford | http://www.io7m.com
